This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Understanding the cellular mechanisms mediating emotional regulation [unreadable]both aversive and appetitive - is of critical importance for a variety of psychiatric disorders, such as Posttraumatic Stress Disorder (PTSD) and Drug Abuse. Through a combination of anatomical, behavioral, molecular, and genetic techniques, our experiments have the potential to resolve an outstanding issue in the role of Brain Derived Neurotrophic Factor [unreadable]a peptide known to be involved in emotional regulation- within the Prefrontal Cortex in modulating expression of appetitive and aversive memories, and extinction of those memories. We have begun to test the hypothesis that a) BDNF-dependent plasticity in the prelimbic cortex is necessary for modulating the expression of previously learned fear.